Annexin 7 mobilizes calcium from endoplasmic reticulum stores in brain

AbstractMobilization of intracellular calcium from inositol-1,4,5-triphosphate (IP3)-sensitive endoplasmic reticulum (ER) stores plays a prominent role in brain function. Mice heterozygous for the annexin A7 (Anx7) gene have a profound reduction in IP3 receptor function in pancreatic islets along with defective insulin secretion. We examined IP3-sensitive calcium pools in the brains of Anx7 (+/−) mice by utilizing ATP/Mg2+-dependent 45Ca2+ uptake into brain membrane preparations and tissue sections. Although the Anx7 (+/−) mouse brain displayed similar levels of IP3 binding sites and thapsigargin-sensitive 45Ca2+ uptake as that seen in wild-type mouse brain, the Anx7 (+/−) mouse brain Ca2+ pools showed markedly reduced sensitivity to IP3. A potent and saturable Ca2+-releasing effect of recombinant ANX7 protein was demonstrated in mouse and rat brain membrane preparations, which was additive with that of IP3. We propose that ANX7 mobilizes Ca2+ from an endoplasmic reticulum-like pool, which can be recruited to enhance IP3-mediated Ca2+ release

Multi-timescale Solar Cycles and the Possible Implications

Based on analysis of the annual averaged relative sunspot number (ASN) during 1700 -- 2009, 3 kinds of solar cycles are confirmed: the well-known 11-yr cycle (Schwabe cycle), 103-yr secular cycle (numbered as G1, G2, G3, and G4, respectively since 1700); and 51.5-yr Cycle. From similarities, an extrapolation of forthcoming solar cycles is made, and found that the solar cycle 24 will be a relative long and weak Schwabe cycle, which may reach to its apex around 2012-2014 in the vale between G3 and G4. Additionally, most Schwabe cycles are asymmetric with rapidly rising-phases and slowly decay-phases. The comparisons between ASN and the annual flare numbers with different GOES classes (C-class, M-class, X-class, and super-flare, here super-flare is defined as $\geq$ X10.0) and the annal averaged radio flux at frequency of 2.84 GHz indicate that solar flares have a tendency: the more powerful of the flare, the later it takes place after the onset of the Schwabe cycle, and most powerful flares take place in the decay phase of Schwabe cycle. Some discussions on the origin of solar cycles are presented.Comment: 8 pages, 4 figure

Multiwavelength studies of MHD waves in the solar chromosphere: An overview of recent results

The chromosphere is a thin layer of the solar atmosphere that bridges the relatively cool photosphere and the intensely heated transition region and corona. Compressible and incompressible waves propagating through the chromosphere can supply significant amounts of energy to the interface region and corona. In recent years an abundance of high-resolution observations from state-of-the-art facilities have provided new and exciting ways of disentangling the characteristics of oscillatory phenomena propagating through the dynamic chromosphere. Coupled with rapid advancements in magnetohydrodynamic wave theory, we are now in an ideal position to thoroughly investigate the role waves play in supplying energy to sustain chromospheric and coronal heating. Here, we review the recent progress made in characterising, categorising and interpreting oscillations manifesting in the solar chromosphere, with an impetus placed on their intrinsic energetics.Comment: 48 pages, 25 figures, accepted into Space Science Review

A Pre-Landing Assessment of Regolith Properties at the InSight Landing Site

This article discusses relevant physical properties of the regolith at the Mars InSight landing site as understood prior to landing of the spacecraft. InSight will land in the northern lowland plains of Mars, close to the equator, where the regolith is estimated to be ≥3--5 m thick. These investigations of physical properties have relied on data collected from Mars orbital measurements, previously collected lander and rover data, results of studies of data and samples from Apollo lunar missions, laboratory measurements on regolith simulants, and theoretical studies. The investigations include changes in properties with depth and temperature. Mechanical properties investigated include density, grain-size distribution, cohesion, and angle of internal friction. Thermophysical properties include thermal inertia, surface emissivity and albedo, thermal conductivity and diffusivity, and specific heat. Regolith elastic properties not only include parameters that control seismic wave velocities in the immediate vicinity of the Insight lander but also coupling of the lander and other potential noise sources to the InSight broadband seismometer. The related properties include Poisson’s ratio, P- and S-wave velocities, Young’s modulus, and seismic attenuation. Finally, mass diffusivity was investigated to estimate gas movements in the regolith driven by atmospheric pressure changes. Physical properties presented here are all to some degree speculative. However, they form a basis for interpretation of the early data to be returned from the InSight mission.Additional co-authors: Nick Teanby and Sharon Keda

Near-Optimal Hot-Potato Routing on Trees

In hot-potato (deflection) routing, nodes in the network have no bu#ers for packets in transit, so that some conflicting packets must be deflected away from their destinations. In this work, we study one-tomany batch routing problems on arbitrary tree topologies with n nodes. The routing time of a routing algorithm is the time for the last packet to reach its destination. Denote by rt the optimal routing time for a given routing problem

Parallel Prefix Computation in the Recursive Dual-Net

Abstract. In this paper, we propose an efficient algorithm for parallel prefix computation in recursive dual-net, a newly proposed network. The recursive dual-net RDN k (B) for k> 0 has (2n0) 2k /2 nodes and d0 + k links per node, where n0 and d0 are the number of nodes and the node-degree of the base network B, respectively. Assume that each node holds one data item, the communication and computation time complexities of the algorithm for parallel prefix computation in RDN k (B), k> 0, are 2 k+1 − 2 + 2 k ∗ Tcomm(0) and 2 k+1 − 2 + 2 k ∗ Tcomp(0), respectively, where Tcomm(0) and Tcomp(0) are the communication and computation time complexities of the algorithm for parallel prefix computation in the base network B, respectively

Successful treatment of Epstein–Barr virus–associated primary central nervous system lymphoma due to post-transplantation lymphoproliferative disorder, with ibrutinib and third-party Epstein–Barr virus–specific T cells

Primary central nervous system lymphoma (PCNSL) occurring following organ transplantation (post-transplantation lymphoproliferative disorder [PTLD]) is a highly aggressive non-Hodgkin lymphoma. It is typically treated with high-dose methotrexate-based regimens. Outcomes are dismal and clinical trials are lacking. It is almost always Epstein–Barr virus (EBV) associated. Two patients (CA1-2) presented with EBV-associated PCNSL after renal transplant. CA1 was on hemodialysis and had prior disseminated cryptococcus and pseudomonas bronchiectasis, precluding treatment with methotrexate. CA2 was refractory to methotrexate. Both were treated off-label with the first-generation Bruton's tyrosine kinase inhibitor ibrutinib for 12 months. Cerebrospinal fluid penetration at therapeutic levels was confirmed in CA1 despite hemodialysis. Both patients entered remission by 2 months. Sequencing confirmed absence of genetic aberrations in human leukocyte antigen (HLA) class I/II and antigen-presentation/processing genes, indicating retention of the ability to present EBV-antigens. Between Weeks 10 and 13, they received third-party EBV-specific T cells for consolidation with no adverse effects. They remain in remission ≥34 months since therapy began. The strength of these findings led to an ongoing phase I study (ACTRN12618001541291).</p